s = '              点头 yes， 摇头 no    '
s.strip()
print(s) # 注：原字符串没有变化
t = s.strip()
print (t)
r = t.replace(' ', '')
print (r)

s2 = 'the little Prince the little Boy'
s2.capitalize()
print(s2)
print(s2.capitalize())
print(s2.title())
print(s2.upper())
print(s2.lower())
print(s2.swapcase())
